How Long Can We Live and What Do We Know About the Aging
Process?: An Interview with Longevity Expert S. Mitchell Harman,
M.D., Ph.D. Newman, Isadore; Newman, Carole; McNally, Christopher pp.
Article description |
Full Text PDF (1055KB)
Lonicera maackii (Amur honeysuckle) and Ligustrum vulgare (Common privet) are two exotic shrubs that have naturalized throughout the eastern and midwestern United States. This study examines the influence of topography on the level of invasion of Lonicera maackii and Ligustrum vulgare in a second growth forested glen in southwestern Ohio (Glen Helen, Yellow Springs, OH). The topographic positions compared were east-facing slope, bottomland, and west-facing slope using twelve 100 m transects through each of the three habitats for a total of 36 transects. L. maackii andZ. vulgare plants were counted in ten 3 x 3 m quadrats along each transect for a total of 120 quadrats per topographic position. Two-way analysis of variance compared interaction between topography and numbers of plants in three size classes (small, medium, large). Average density of L. maackii for all size classes was 1136 plants/ha. East-facing slopes were most heavily invaded with 497 plants/ha; there were 238/ha in the bottomland; 401/ha on the west-facing slopes. East- facing slopes are close to town, one of the original sources of seed. West-facing slopes are surrounded by farmland, fence rows, and farmhouses, a second source of seed. West-facing slopes have significantly fewer large L. maackii and L. vulgare than eastfacing slopes but it may only be a matter of time until they are as heavily colonized as the east-facing. For now, the native species of the bottomland are able to compete successfully against L. maackii. Without management, however, colonization ofZ. maackii in the bottomland may progress. L. vulgare, overall, is not as invasive in this woodland setting asZ. maackii.
(2001-12) Iverson, Aaron L.; Iverson, Louis R.; Eshita, Steve
We tested the role of salicylic acid (SA) and jasmonic acid (JA) in altering the tomato plant's defense against herbivory by tobacco hornworm. Treatments of SA or JA were topically applied to tomato plants, hornworm consumption was allowed to proceed for 12 days, and harvest analyses were performed. Measurements taken included a subjective plant rating (1-10 score), plant dry mass, caterpillar mass, and the number of times the caterpillars fell off the plant. Results showed significant effects of exogenously applied SA and JA on the defense of tomato plants against insect herbivory. Plants treated with SA had little resistance to the feeding caterpillars and the plant lost more biomass to them. JA, in contrast, apparently increased the defensive mechanisms of the plant, resulting in lower caterpillar growth and increased caterpillar detachment from plants. The data are consistent with a model where JA, endogenous or exogenously applied, is necessary for defense against insect herbivory and SA disrupts JA biosynthesis and/or pool accumulation.
(2001-12) Kaplan, David H.; Bender, Carrie; Kigochie, Petronella; Pleasants, James
The urban environment in Ohio has changed dramatically over the last thirty years, with areas of improvement and areas of degradation. This paper seeks to inventory the state of Ohio's environment in terms of a set of key environmental indicators: conversion of open spaces, changes in farmland acreage, loss of wildlife habitat, number of endangered plant species, brownfields, air pollutants, and lake quality. We attempt to accomplish two broad objectives in this paper. First, we look at the geographic pattern of these environmental quality indicators, paying particular attention to the major metropolitan areas. Second, we examine how these aspects of environmental quality have changed over the past two or three decades, noting areas of progress and of deterioration. Overall we find that air quality in Ohio has clearly improved, although Ohio lags behind other states. The expansion of urbanization has resulted in environmental degradation especially in regard to declining wetland acreage, farmland, and wildlife habitat. Water quality and parkland acreage show no clear change in either direction. We find throughout a need for more comprehensive data on these environmental indicators, so that policy makers can understand what needs to be accomplished.